<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body bgcolor="orange">
		<form action="f.jsp" method="post">
		选择计算和的方式:
		<select name="s1">
		<option value="a">计算1到n的连续和</option>
		<option value="b">计算1到n的平方和</option>
		<option value="c">计算1到n的立方和</option>
		</select><br>
		
		选择n的值:
		<select name="s2">
		<option value="20">n=20</option>
		<option value="40">n=40</option>
		<option value="50">n=50</option>
		<option value="100">n=100</option>
		</select>
		<br>
		<input type="submit" value="提交">
		</form>
</body>
</html>